Keyboard



FIG. 1 is a front perspective view of a keyboard;

FIG. 2 is a front elevational view of the keyboard;

FIG. 3 is a left elevational view thereof;

FIG. 4 is a right elevational view thereof;

FIG. 5 is a top plan view thereof; and,

FIG. 6 is a bottom plan view thereof.

The broken line border shown in FIGS. 1 and 2 immediately surrounding the keys represent the bounds of the claimed design, while all other lines are directed to environment and form no part of the claimed design. 

We claim the ornamental design for a keyboard, as shown and described. 